1. Field of the Invention
This invention relates to a time data receiving apparatus which receives the radiowaves containing a time code, extracts time data from the radiowaves, and corrects the time on the basis of the time data.
2. Description of the Related Art
At present, in Germany, England, Switzerland, Japan, etc., where the radiowaves containing a time code are being transmitted, radio-controlled timepieces have been put to practical use which receive the radiowaves, extract time data from the radiowaves, and corrects the current time data in the current time count circuit on the basis of the time data.
Furthermore, for example, a radio-controlled timepiece provided with an alarm function that goes off at the alarm time previously set has been disclosed in U.S. Pat. No. 5,083,123.
In such a radio-controlled timepiece with an alarm function, the alarm time data previously set is compared with the current time data in the current time count circuit every minute, and the alarm is given when they coincide with each other.
Therefore, even when a radiowave correction timing has occurred immediately before the current time data in the current time count circuit reaches the alarm time data, and the received accurate time data becomes the time data behind the alarm time, this time data will still be used to correct the current time data in the current time count circuit. As a result, the alarm time has passed, so that the coincidence of the alarm time data with the current time data in the current time count circuit cannot be sensed, and consequently the user is not informed of the alarm time.
The idea has been proposed that such a radio-controlled timepiece is provided with a timer 10 function of informing the user when the preset time has been reached.
A case will be considered where the elapsed time is measured using a radio-controlled timepiece with such a timer function.
For example, it is assumed that the user plans to start specific work at 4:50 p.m. and end at 5:20, sets the timer for 30 minutes, and starts the timer function at 4:50 to inform him at 5:20.
In the case where the radiowaves containing a time code is received at 5:00, the time data is extracted from the radiowaves, and the current time data in the current time count circuit is corrected on the basis of the time data, when the user is informed after the time set in the timer has elapsed, the current time data in the current time count circuit is other than 5:20 and consequently the time different from 5:20 is displayed. For this reason, the user may think that he must have set the wrong time in the timer, any time other than 30 minutes, or he may doubt the accuracy of the radio-controlled timepiece with the timer function.